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UNITED STATES JOHN B. CORNELL, OF NEW YORK, N. Y.

FIREPROOF FLOOR.

Specification of Letters Patent No. 22,939, dated February 15, 1859.

To all whom it muy concern:

Be it known that I, JOHN B. CORNELL, of the city, county, and State of New York, have invented a new and economical method of forming a tireproof foundation upon a series of wooden gir-ders for the reception of a flooring surface composed of boards or other suitable materials; and I do hereby declare that the following is a full and eX- act description thereof, reference being had to the accompanying drawings, making a part of this specification.

Figure 1, is a section of one of my improved fire-proof floors in the line of Fig. 2, and Fig. 2, is a section in the line gf, y, of Fig. 1. Fig. 3, is a modification of Fig. 1.

In constructing my improved fire-proof foundation for a floor upon a series of wooden girders, (a, 4,) I first secure to the upper edges of said girders a continuous covering of plaster-supporting met-allie sheets (d, d.) The said metallic sheets may either rest directly upon the upper edges of the girders (a, (6,) or thimbles g, g, may be interposed between the two, as represented in the drawings. A series of wooden strips t, o, are then placed, at suitable intervals, upon the upper surface of the said plaster supporting sheets, and are secured thereto either in the manner represented in the accompanying drawings or by any other suitable means. The next step in said invention is to thoroughly fill all the cavities in the metallic sheets d, al, above and below, with moistened plaster of paris, (6,) or some other nonconducting nre-proof composition, taking special and particular pains to force the said composition into all the spaces between upper surfaces of said girders and the under surfaces of the metallic sheets. If deemed necessary, the lire-proof composition may be laid upon the upper sides of the metallic sheets (d, (L) in suflicient quant-ity to raise its upper surface to a level with the upper surfaces of the strips Z), Z), or a little above the same, as shown in the drawings.

Having thus constructed a perfectly lireproof foundation for the flooring boards c. c, I secure the said boards to the strips Z), b, by either of the methods represented in the drawings, or by any other method that may be deemed expedient.

I employ screws instead of nails as the means of securely retaining the llooring boards in their proper position, upon the fire-proof foundation, for the reason that `they can be used without loosening the strips 7J, l), or producing any fractures in the lire-proof composition which incloses said strips. i

lWhat I claim as my invention and desire to secure by Letters Patent, is-

Constructing a lire-proof foundation upon a series of wooden girders for the reception of a flooring surface formed of boards, or other suitable materials, substantially as herein set forth.

The above specication of my new and economical method of constructing lireproof floors, signed and witnessed this 11th day of November, 1858.

JOHN B. CORNELL.

lVitnesses:

A. A. JAYNE, I. L. CADY. 

